An investigation of seed dormancy cycling mechanisms and local adaptations in arabidopsis thaliana

Seeds track environmental signals to avoid unfavorable conditions for germination and match the time of their germination to the growing season. Sensitivities to environmental signals that result in the release or the induction of dormancy differs between genetic backgrounds. In this study, a recombinant inbred lines (RILs) mapping population created between a winter and a summer annual ecotypes of Arabidopsis thaliana was subjected to a dormancy cycling treatment. Ten quantitative trait loci (QTLs) were identified for different aspects of dormancy cycling within the phenotypic variation of the population response. The results reveal that DOG1 controls the germination potential at 25◦C under the influence of primary dormancy (PD) and secondary dormancy (SD) after the cold incubation of seeds at 5◦C. However, the germination potential at 10◦C under the influence of SD after the warm incubation of seeds at 25◦C is not controlled by DOG1 (the warm incubation follows the cold incubation). A candidate gene within Peak 5, ATHB-5, is proposed to be in control of the germination potential after the warm incubation by a network analysis of publicly available transcriptome data. ATHB-5 is a potential source of local adaptation in regulation of seed dormancy cycling. The identification of dormancy cycling QTLs, the analysis of a newly generated double mutant between dog1-2 and mft2, and the results of the network analysis propose a new perspective on the regulation of dormancy cycling in Arabidopsis thaliana.